Brake shoe



. Aug. 29, 1933. RFEVANS muxa'skoz Filed larch 20, 1931 Patented Aug 29,1933 BRAKE SHOE Edwin E. Evans, Chicago, 111. Application March 20,1931. Serial No. 524,011

2 Claims.

formed from a rolled section of standard shape.

and provided with an integral actuating portion. It is an additionalobject to provide a shoe of this character in which the actuating faceis integrally connected to and fully supported by a web of the rolledsection.

It is a further object to provide a shoe having an integral hardenedactuating wear face.

Other and further objects will appear as the description proceeds. I

I have shown certain preferred embodiments of my invention in theaccompanying drawing,-

in which- Figure 1 is an elevation of my improved shoes applied to abrake assembly, the brake drum being cut away to show the interiorparts;

Figure 2 is a similar view of a single brake shoe on an enlarged scale;

Figure 3 is a view of Figure 2 as seen from above; v

Figure 4. is a view of Figure 2 as seen from below;

Figure 5 is a view of Figure 2 as seen from the left;

Figure 6 is a section of Figure 2 on line 6-6;

Figure '7 is a section of Figure 2 on line 7-7; Figure 8 is a sectionsimilar to Figure 6 showing a modified form of construction; and

Figure 9 is a view similar to Figure 8 showing a further modified form.

In Figure 1 the backing plate 11 is shown provided with bolts 12 bywhich it may be so cured to a steering knuckle (not shown). The

backing plate 11 carries a housing 13 which sup ports an adjustablebrake shoe pivot pin 14. The bearing ends 15 of the shoes 16 passthrough slots in the housing 13 to engage in grooves in the pin is. Theshoes 16 are T-shaped in cross section, being provided with thecylindrical flange 17 and the inwardly extending web 18. The flange 17carries the brake lining 19 adapted to engage the brake drum 20. Thesprings 21 are connected at one end to the shoes 16 and at the other endto the backing plate 11 so that they serve to retract the shoes fromengagement with the brake drum 20. The springs may impart angularthrusts to the shoes tending to urge them toward the backing plate, .andthe webs of the shoes may have raised portions 40, 10 for engaging thebacking plate. The portions 40 therefore require 'machiningof only smallsurfaces.

The lower ends of the shoes, as shown, are provided with bent up ends 22which serve as actuating faces to engage the operating cam 23 carried bybrake operating shaft 24. Both the web 16 and flange 17 are bent orforged so that the flange throughout its extent, including the bent upportion, is integrally and permanently connected with the web.

In one method of manufacture, the shoes are formed from straight T-bars.These bars are first sawed'to give pieces of the proper length for thedesired shoes. Then the webs have outer portions adjacent the ends ofthe blanks cut 5 away on lines such as to eliminate excess metal. Theends of the blanks are then bent up, the metal of the web being forgedor swaged to bring it to the form shown in the drawing. There are noedges to be joined by the forging or swaging and there is no welding.The metal of the web is caused to flow to form the continuous web shown.I

In the form shown the web 16 is of a depth g5 similar to the depth ofthe wear face 22 so that this face is supported by the web throughoutits height. The flange portion of the blank which forms the .actuatingface 22 is also deformed during the forming operation, being curved incross section as clearly shown at 23 of Figure 4. Also where the shoe isto be used in a structure in which the shoe is in a plane at an angle tothe plane of the swiveling axis, the curved portion of the bearing facemay be formed on an angle as best shown in Figure 5. Due to this curvedformation the edges of the flanges extend inwardly as shown at 24 and 25of Figure 5.

The upper or pivot end 15 of the shoe may be formed by the same type ofoperations as the acm tuating end. The pivot end 15 has an end face 26cut on an angle as shown in Figure 3 so as to fit in the angular groovesin the pivot pin 14 whereby axial movement of the pin will adjust theshoes.

A portion of the web 16 is shown bent over to give a bearing face 2'7for a centralizer 28. This centralizer is shown in Figure 1 as a conicalheaded stud threaded into the backing plate 11.

The shoes may be suitably heat treated as plete. The pivot ends and wearfaces 23 may be hardened to resist wear, by the cyanide process 7 forexample.

While the shoes have been described so far as being formed of T-shapedrolled section, it may be found desirable in large sizes and with wideshoes to use sections having a plurality of inwardly extending webs.Figure 6 shows a section having a flange and a pair of spaced webs 31and 32. Figure 9 shows a channel section with a base 33 and legs 34 and35; Sections such as these with a pluralityof webs permit strengtheningthe flangeat a' plurality of 'points and also permit equivalent rigiditywith webs of less depth than would be necessary with a'fl'esser numberof webs. The webs of less deptlipermit greater clearances in theassembly and also facilitate the forming operations of the ends of theshoes.

The forms of construction shown are to be taken as illustrative only, asthe improved brake shoe is capable of variations and' chan e to meetdiffering requirements. and I contemplate such desired, after theforming operations are comchanges and modifications as come within thespirit and scope of the appended claims.

I claim: V

1. A brake shoe comprising a unitaryrrolled section having a cylindricalflange and an inwardly extending web, a continuous portion of the flangeintegrally connected to the web throughout its extent being bentinwardly to form a cam contact face, the web being of a depthsubstantially'equal to the depth of the inwardly extending flange anddirectly, supporting said flange.

2. A brake assembly comprising a unitary rolled section brake shoehaving a cylindrical flange and an inwardly extending web, a continuousportion of the flange integrally connected to the web throughout itsextent being bent inwardly, the inwardly extending flange forming a camcontact face, said face being hardened to resist wear, and a brakeoperating cam engaging said surface.

EDWIN R. EVANS.

